What is it called when dissimilar metals react with each other in an aqueous solution?

When dissimilar metals react with each other in an aqueous solution, this phenomenon is known as galvanic corrosion. This process occurs when two different metals are electrically connected in a conductive environment, such as water. In this scenario, one metal becomes the anode (where oxidation occurs), and the other becomes the cathode (where reduction takes place).

The difference in electrochemical potential between the two metals leads to an electrochemical reaction, which ultimately results in the deterioration of the more anodic metal—the one that is more likely to oxidize. This is why understanding galvanic corrosion is particularly important in water treatment and distribution systems, where metals of varying properties may come into contact.

While electrolysis involves the use of electrical currents to drive a chemical reaction, and oxidation refers specifically to the loss of electrons by a substance, these terms do not specifically address the interaction between different metals in the presence of an electrolyte. Corrosion is a broader term that includes various types of metal degradation, but galvanic corrosion is a specific type triggered by the interaction of dissimilar metals in an electrolyte, making it the most accurate answer in this context.